The present invention relates to the installation and/or removal of an electrical terminator (such as an elbow terminator), relative to an electrical bushing, and especially to a tool for augmenting a force manually applied in order to effect such installation and/or removal.
Electrical distribution equipment, such as transformers, typically include electrical bushings which must be connected to electrical cables leading to external electrical equipment. The bushings are mounted in a wall of the electrical equipment and have their outer ends arranged to be connected to the electrical cables. One type of connector used for this purpose is an elbow terminator. The elbow and bushing are to be mated, and held releasably together by an internal annular ring-and-groove coupling. A proper mating of the elbow and bushing to bring the ring into engagement with the groove can require considerable force. That is also the case when it is desired to remove the elbow. In fact, after a prolonged period of attachment, a strong bond can develop between the elbow and bushing which is extremely difficult to overcome.
The amount of force necessary to install and remove an elbow relative to a bushing is of concern, because traditionally those operations have been performed by manual effort. Although tools, e.g., so-called shotgun sticks, have been used to position the elbow in alignment with the bushing, the actual insertion and removal effort is performed manually by an operator. The purpose of the shotgun stick is to enable the operator to manipulate the elbow from a safe distance, i.e., in isolation from the electrical current.
Tools have been previously proposed to provide a force which aids in the removal of a stuck or seized-on elbow, but such devices have been of limited use, because (1) they are not able to assist in the installation of an elbow, and (2) they require, for operation, that the transformer wall include a flat contact area in the immediate vicinity of the bushing, which flat contact area is not present in all transformers.
It would be desirable, therefore, to provide a tool which will augment manual forces applied during both the installation and removal of electrical terminators, and which does not require the presence of a flat contact area on the transformer wall.